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authorDavid Hildenbrand <david@redhat.com>2021-04-22 12:08:20 +0200
committerDavid Hildenbrand <david@redhat.com>2021-09-03 18:42:01 +0200
commit8d0920bde5eb8ec7e567939b85e65a0596c8580d (patch)
treecdba733cd679ff5527daab0e8303a4da97adec4b /mm/mmap.c
parentbinfmt: remove in-tree usage of MAP_DENYWRITE (diff)
downloadlinux-dev-8d0920bde5eb8ec7e567939b85e65a0596c8580d.tar.xz
linux-dev-8d0920bde5eb8ec7e567939b85e65a0596c8580d.zip
mm: remove VM_DENYWRITE
All in-tree users of MAP_DENYWRITE are gone. MAP_DENYWRITE cannot be set from user space, so all users are gone; let's remove it. Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Christian K├Ânig <christian.koenig@amd.com> Signed-off-by: David Hildenbrand <david@redhat.com>
Diffstat (limited to 'mm/mmap.c')
-rw-r--r--mm/mmap.c27
1 files changed, 3 insertions, 24 deletions
diff --git a/mm/mmap.c b/mm/mmap.c
index ca54d36d203a..589dc1dc13db 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -148,8 +148,6 @@ void vma_set_page_prot(struct vm_area_struct *vma)
static void __remove_shared_vm_struct(struct vm_area_struct *vma,
struct file *file, struct address_space *mapping)
{
- if (vma->vm_flags & VM_DENYWRITE)
- allow_write_access(file);
if (vma->vm_flags & VM_SHARED)
mapping_unmap_writable(mapping);
@@ -666,8 +664,6 @@ static void __vma_link_file(struct vm_area_struct *vma)
if (file) {
struct address_space *mapping = file->f_mapping;
- if (vma->vm_flags & VM_DENYWRITE)
- put_write_access(file_inode(file));
if (vma->vm_flags & VM_SHARED)
mapping_allow_writable(mapping);
@@ -1788,22 +1784,12 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
vma->vm_pgoff = pgoff;
if (file) {
- if (vm_flags & VM_DENYWRITE) {
- error = deny_write_access(file);
- if (error)
- goto free_vma;
- }
if (vm_flags & VM_SHARED) {
error = mapping_map_writable(file->f_mapping);
if (error)
- goto allow_write_and_free_vma;
+ goto free_vma;
}
- /* ->mmap() can change vma->vm_file, but must guarantee that
- * vma_link() below can deny write-access if VM_DENYWRITE is set
- * and map writably if VM_SHARED is set. This usually means the
- * new file must not have been exposed to user-space, yet.
- */
vma->vm_file = get_file(file);
error = call_mmap(file, vma);
if (error)
@@ -1860,13 +1846,9 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
vma_link(mm, vma, prev, rb_link, rb_parent);
/* Once vma denies write, undo our temporary denial count */
- if (file) {
unmap_writable:
- if (vm_flags & VM_SHARED)
- mapping_unmap_writable(file->f_mapping);
- if (vm_flags & VM_DENYWRITE)
- allow_write_access(file);
- }
+ if (file && vm_flags & VM_SHARED)
+ mapping_unmap_writable(file->f_mapping);
file = vma->vm_file;
out:
perf_event_mmap(vma);
@@ -1906,9 +1888,6 @@ unmap_and_free_vma:
charged = 0;
if (vm_flags & VM_SHARED)
mapping_unmap_writable(file->f_mapping);
-allow_write_and_free_vma:
- if (vm_flags & VM_DENYWRITE)
- allow_write_access(file);
free_vma:
vm_area_free(vma);
unacct_error: